Whistle Lake Dam Reservoir Report

Last Updated: December 13, 2025

Whistle Lake Dam, located in Anacortes, Washington, was completed in 1925 for the primary purpose of recreation.


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Summary

This earth dam stands at a hydraulic height of 15 feet and a structural height of 7 feet, with a length of 75 feet. With a maximum storage capacity of 200 acre-feet and a normal storage of 140 acre-feet, the dam serves as a fish and wildlife pond in addition to providing recreational opportunities for visitors.

Despite its historical significance and recreational value, Whistle Lake Dam has a high hazard potential and is currently assessed to be in poor condition. The last inspection in August 2017 highlighted the need for improvements and maintenance to ensure the safety and integrity of the structure. The Washington Department of Ecology regulates the dam, overseeing its permitting, inspection, and enforcement to mitigate risks and protect the surrounding community and environment.

As water resource and climate enthusiasts, it is crucial to recognize the importance of maintaining and enhancing infrastructure like Whistle Lake Dam to preserve water resources and support ecosystem health. By addressing the dam's poor condition and implementing risk management measures, stakeholders can ensure the safety of the dam while continuing to enjoy its recreational and ecological benefits in the Skagit County area.

Year Completed

1925

Dam Length

75

Primary Dam Type

Earth

Hydraulic Height

15

Drainage Area

492

Nid Storage

200

Structural Height

7

Hazard Potential

High

Foundations

Unlisted/Unknown

Nid Height

15
       
Seasonal Comparison

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.

Hazard Potential Classification

High
Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.